计算机数据安全存储技术及应用

数据安全是计算机安全问题的核心,对于很多具有高度保密要求的单位,安全地存储重要数据,并且在不需要这些数据时作彻底销毁不被他人恢复是至关重要的。本文详细介绍了数据安全存储技术的发展现状,并结合典型的企业信息安全防护体系设计进一步阐述了如何为具有一定保密要求的部门建立可靠的数据安全防护系统。此外,本文从数据存储和销毁的原理上进行了详细分析,并给出了应用软件及案例的测试说明,提出了安全销毁数据的详细解决方法。     

Asymptotic and robust stability of T‐S fuzzy genetic regulatory networks with time‐varying delays

In this paper, we propose and investigate a new general model of fuzzy genetic regulatory networks described by the Takagi–Sugeno (T‐S) fuzzy model with time‐varying delays. By using a Lyapunov functional approach and linear matrix inequality (LMI) techniques, the stability criteria for the delayed fuzzy genetic regulatory networks are expressed as a set of LMIs, which can be solved numerically by LMI toolbox in Matlab. Two fuzzy genetic network example are given to verify the effectiveness and applicability of the proposed approach. Copyright © 2011 John Wiley & Sons, Ltd.     

Adaptive fuzzy dynamic surface control for a class of perturbed nonlinear time-varying delay systems with unknown dead-zone

In this paper,adaptive dynamic surface control(DSC) is developed for a class of nonlinear systems with unknown discrete and distributed time-varying delays and unknown dead-zone.Fuzzy logic systems are used to approximate the unknown nonlinear functions.Then,by combining the backstepping technique and the appropriate Lyapunov-Krasovskii functionals with the dynamic surface control approach,the adaptive fuzzy tracking controller is designed.Our development is able to eliminate the problem of "explosion of complexity" inherent in the existing backstepping-based methods.The main advantages of our approach include:1) for the n-th-order nonlinear systems,only one parameter needs to be adjusted online in the controller design procedure,which reduces the computation burden greatly.Moreover,the input of the dead-zone with only one adjusted parameter is much simpler than the ones in the existing results;2) the proposed control scheme does not need to know the time delays and their upper bounds.It is proven that the proposed design method is able to guarantee that all the signals in the closed-loop system are bounded and the tracking error is smaller than a prescribed error bound,Finally,simulation results demonstrate the effectiveness of the proposed approach.     

一种简便的饮用水除铀方法及其机理

本文介绍一种利用原水中含有的无机盐,加入廉价的化学试剂除去饮用水中微量铀的简便方法。并对其除铀机理进行了探讨,证明除铀主要是以软化水过程中产生的氢氧化镁表面吸附共沉淀机理进行的。     

高温眼镜阀的创新研究与应用

转炉煤气干法除尘工艺是钢铁企业重要的节能降耗先进技术,眼镜阀是与之配套的关键设备,近年来,转炉煤气干法除尘工艺眼镜阀配置大部分采用从国外引进,费用高。文章基于TRIZ理论和方法,对转炉煤气干法除尘工艺眼镜阀进行了深入的研究,并在高温密封、液压控制、阀门自动复位等方面采用了新的方法。创新成果成功地应用于首钢京唐炼钢工程,促进了转炉煤气干法除尘工艺技术的推广。     

信息融合技术在变压器油气识别故障诊断中的研究

变压器故障分为放电性故障和过热性故障两大类别,它们均会在变压器油中有所反映。本文通过对变压器油中主要气体的分析,判断变压器的故障类型。具体方法是:利用改进算法的BP网络和信息融合技术,以变压器油中五种主要特征气体作为神经网络的输入,以六种变压器状态作为相应的输出,通过加入动量因子,可以提高学习率系数,充分发挥改进算法的BP网络具有自适应学习能力的优势。仿真测试结果表明,本方法能够在较大范围内准确有效地进行变压器的故障诊断。     

基于单片机直接驱动段式LCD的驱动模块设计

提出并设计了一种基于单片机直接驱动段式LCD的驱动模块,使用简单的附加电路实现了对背极信号的有效控制。该电路与程序相配合,实现了偏置电压控制法,交流驱动信号的产生由背极信号与段极信号的配合形成,且交流驱动信号的直流分量的平均值为零。该驱动模块具有一般性,适用于需计数、计时、状态提示等LCD显示的电子类产品中。     

等离子体湮没离子注入

本文扼要地介绍了等离子体湮没离子注入的基本原理，特点，应用效果及发展趋向。     

粉末冶金TiAl合金排气门的研制

利用元素粉末冶金方法制备了TiAl合金排气阀。为提高排气门杆部的致密度、均匀度 ,设计了特有的径向热压工艺 ,并从理论上分析了与该工艺相关的压坯密度、致密化和应力变化规律。制备出高径比为 10 .7,密度为 3.79g/cm3 的粉末冶金TiAl合金汽车发动机排气门